OPINION
HECHT, Justice.Several courts of appeals have disagreed over the effect of our decision in Varela v. American Petrofina Co., 658 S.W.2d 561 (Tex.1983). Three courts of appeals, and the United States Court of Appeals for the Fifth Circuit, have concluded that Varela does not preclude a defendant in a personal injury lawsuit from introducing evidence that the negligence of plaintiff’s employer caused the accident, even though the employer is shield*751ed from liability by the Workers’ Compensation Law. Williams v. Union Carbide Corp., 734 S.W.2d 699 (Tex.App.—Houston [1st Dist.] 1987, writ ref'd n.r.e.); Sappington v. Younger Transp., Inc., 758 S.W.2d 866 (Tex. App.—Corpus Christi 1988, writ denied); Agricultural Warehouse, Inc. v. Uvalle, 759 S.W.2d 691 (Tex.App.—Dallas 1988), writ denied per curiam, 779 S.W.2d 68 (Tex.1989) (noting but not addressing another issue); Turlington v. Phillips Petroleum Co., 795 F.2d 434 (5th Cir.1986). At least one other court, in this case and in a prior decision, has reached the opposite conclusion. 821 S.W.2d 406 (Tex.App.—Tyler 1991); W.B. Hinton Drilling Co. v. Zuniga, 784 S.W.2d 442 (Tex.App.—Tyler 1989, no writ). We granted writ of error to resolve this conflict. We disagree with the court of appeals in this case and therefore reverse its judgment and remand the case for further proceedings. Because it may be necessary to retry this case, we also consider the parties’ arguments concerning the manner in which this ease should be submitted to the jury.
I
Tyler Pipe Industries, Inc. operates a foundry where pipe is made using silica flour and silica sand. Arthur B. Lee began working at the foundry in 1964, when he was eighteen years old, and remained in that employment until 1972. For many years, including the entire period during which Lee worked at the foundry, the pipe-making process utilized there produced a powder of minute particles of silica which filled the air in the foundry. Lee and other workers inhaled this dusty air.
Inhaling silica dust may cause respiratory disease, a risk that has been recognized for more than a century and of which Tyler Pipe was well aware. Trade organizations like the National Foundry Association, to which Tyler Pipe belonged, published materials which Tyler Pipe received, warning of the dangers of using silica in foundries and recommending methods to lessen or prevent such dangers. Despite its knowledge of the risks of working around silica dust, Tyler Pipe took few precautions to safeguard its employees. It had a policy of requiring workers to wear respirators in the area of the plant where the silica material was mixed with water and sprayed, an area where Lee sometimes worked, but it is unclear how strictly that policy was enforced. There was no such policy in other areas of the plant, which were also very dusty. The dust bothered Lee, but since Tyler Pipe did not require him to wear any protective gear, and because of the heat in the foundry, he rarely used a mask and used a respirator only once.
One of Tyler Pipe’s suppliers of silica products was Dresser Industries, Inc. Dresser’s products were delivered to Tyler Pipe sometimes in bulk form and sometimes in bags. Although Dresser, too, was aware of the risks of inhaling silica dust, its bags did not bear a warning label.
Several years after leaving Tyler Pipe, Lee began to develop various respiratory diseases, including what was eventually diagnosed as silicosis. In 1987, Lee joined seventeen other employees of Tyler Pipe in a suit against Dresser and other suppliers of silica products, alleging that defendants’ failure to warn them of the risks related to the use of silica products caused their injuries. Tyler Pipe was immune from liability to plaintiffs or defendants because plaintiffs’ injuries were covered by workers’ compensation insurance. Tex.Rev.Civ.StatAnn. art. 8808-4.01, -4.04 (Vernon Supp.1993) (formerly Tex.Rev.Civ.Stat.Ann. art. 8306, § 3, Act approved June 10, 1963, 58th Leg., R.S., ch. 437, § 1, 1963 Tex.Gen.Laws 1132, amended and restructured without substantial change by Act approved May 17, 1983, 68th Leg., R.S., ch. 131, § 1, 1983 Tex.Gen.Laws 613, repealed and restructured without substantial change by Act of 1989, 71st Leg., 2d C.S., ch. 1, §§ 4.01, 4.04,1989 Tex.Gen.Laws 1, 32-33, eff. Jan. 1, 1991). By the time the case came to trial in 1990, Lee was the only remaining plaintiff, the others having settled, and Dresser was the only defendant. The case was tried on a single legal theory— strict liability — with Lee contending that the absence of warning labels on the bags of Dresser’s silica products rendered them unreasonably dangerous.
The trial court, relying primarily on Vare-la, excluded all evidence offered by Dresser *752to show that Tyler Pipe’s failure to require Lee to take precautions to protect himself, such as wearing a mask or respirator, was the sole cause of Lee’s injuries. The trial court also refused Dresser’s request to give the jury the following instruction regarding sole cause:
There may be more than one proximate cause of an event, but if an act or omission of any person not a party to the suit was the “sole proximate cause” of an occurrence, then no act or omission of any other person could have been a proximate or producing cause.
In addition, the trial court excluded certain evidence that Lee’s own negligence caused his injuries, and refused to submit an issue on contributory negligence to the jury.
The jury found that Lee suffered damages totaling $754,444.43, caused 96% by Dresser’s products and 4% by those of a settling defendant. The trial court rendered judgment against Dresser for 96% of the damages found by the jury, plus interest, a total of $755,972.04.
Dresser appealed. The court of appeals agreed with the trial court that Varela barred all evidence of Tyler Pipe’s negligence, even if offered to show that its negligence was the sole cause of Lee’s injuries. The court criticized what it perceived to be the rule of Varela but considered itself bound to follow that case. The court also held that the trial court did not err in refusing to submit contributory negligence to the jury because Dresser did not request an accompanying instruction that Lee had no duty to discover or guard against the dangers involved in using Dresser’s products. The court of appeals affirmed the trial court’s judgment.
Shortly before Dresser filed its petition for writ of error in this Court, Lee died.
II
In Varela, plaintiff sued the owner of the premises where he had been working at the time he fell and injured himself. Since the accident was covered by workers’ compensation insurance, plaintiff’s employer was immune from liability to either plaintiff or defendant. See former TexRev.Civ.Stat.Ann. art. 8306 § 3, now TbxRev.Civ.Stat.Ann. art. 8308-4.01, -4.04. However, the trial court instructed the jury to apportion responsibility among all persons whose negligence caused the accident. The jury assigned plaintiff 15% responsibility, defendant 43%, and plaintiffs employer 42%. The trial court rendered judgment for plaintiff against defendant for only 43% of the damages found by the jury, and plaintiff appealed. This Court summarized the issue raised on appeal and its holding as follows:
The sole question before us is whether an employer’s negligence may be considered in a third-party negligence action brought by an employee arising out of an accidental injury covered by workers’ compensation insurance. We hold that under applicable statutes, the employer’s negligence may not be considered.
658 S.W.2d at 561-562. The Court reasoned that since a claim for contribution against the subscribing employer was barred by the Workers’ Compensation Law, the Comparative Responsibility Law, TexRev.Civ.Stat. Ann. art. 2212a (amended and recodified as Tex.Civ.PRAC. & Rem.Code §§ 33.001-016), did not apply to limit the damages for which defendant was liable to the percentage it was found to have caused. Thus, defendant was required to pay the damages found by the jury reduced only by the percentage caused by the plaintiff. In other words, defendant was required to pay the damages caused by both it and plaintiffs employer.
The only issue addressed in Varela was whether defendant was hable for that part of plaintiffs damages caused by plaintiffs employer. See Magro v. Ragsdale Bros., Inc., 721 S.W.2d 832, 835 (Tex.1986). The language of the opinion must be read in that context. Lee, however, argues that the statement in Varela — “the employer’s negligence may not be considered” — should be read more broadly to prohibit consideration of an employer’s negligence, not solely for the purpose of allocating responsibility, but for any purpose at all. Thus, according to Lee, Varela holds that no evidence of an employer’s negligence is admissible, even if offered for the purpose of showing that only *753the employer, and not the defendant, was at fault. In the abstract, the language of Vare-la may of course be read as broadly as Lee argues it should be; in context, however, the meaning is more limited. The plaintiff in Varela did not contend that all evidence of his employer’s negligence should have been excluded, nor did the defendant contend that the employer’s negligence was the sole cause of the plaintiffs injuries.1 The admissibility of evidence of the employer’s negligence was not raised as an issue or discussed. To the contrary, both the plaintiff and this Court simply assumed that the evidence was properly admitted. The Court’s language must be read in the context of the issues decided. The context of Varela precludes Lee’s convex reading of one phrase from the opinion.
Not only did we not espouse Lee’s broad position in Varela, we should not do so now. If a defendant were unable to show the role of plaintiffs employer in the circumstances of plaintiffs injury, the defendant would be limited in its defense to countering evidence that its negligence caused the injuries. A defendant is entitled to try to con- ' vince the jury that not only did it not cause plaintiffs injuries, but someone else did. A void of evidence concerning the employer’s conduct would leave a logical hiatus in the story presented to the jury. With no one allowed to show what part the employer’s conduct played, the jury would be left to wonder whether anyone other than the defendant could have caused plaintiffs injuries. The court of appeals agreed that the rule urged by Lee had unjust consequences, but felt that it correctly expressed the holding of Varela.2 We agree that the rule is not a good one, but we disagree that it finds expression in Varela.
Dresser was thus entitled to show that Tyler Pipe’s negligence was the sole cause of Lee’s injuries. Dresser offered evidence, which the trial court excluded, to show that Tyler Pipe failed to ventilate its foundry properly and to require employees to wear safety masks. The jury could have concluded from this evidence that Tyler Pipe was negligent and that its negligence was a cause of Lee’s injuries. The fact that Dresser failed to include in the labels on bags of its silica products warnings about risks involved in the use of those products does not preclude a finding that Tyler Pipe’s negligence was the sole cause of Lee’s injuries.
In Technical Chemical Co. v. Jacobs, 480 S.W.2d 602, 606 (Tex.1972), we considered but did not adopt a rebuttable presumption that an adequate warning will be read and that the failure to give an adequate warning is necessarily a cause of injury. Instead, we concluded that even if there were such a presumption, there was sufficient evidence to show that plaintiff would have disregarded any warning given. In Magro v. Ragsdale Bros., Inc., 721 S.W.2d at 834, we did adopt the presumption suggested in Technical Chemical, holding that “it may be rebutted with evidence that the user [of the product] was blind, illiterate, intoxicated at the time of the product’s use, irresponsible, lax in judgment, or by some other circumstances tending to show that the improper use would have occurred regardless of the proposed warnings or instructions.” Employment of this presumption excuses plaintiff from offering self-serving evidence — that yes, he would have followed instructions if *754only they had been given — simply to meet his burden of proof. Once defendant has offered evidence of circumstances tending to show that no warning would have been heeded, an issue arises which can be resolved only by the finder of fact.
In the present case, evidence was adduced at trial that Lee had an eighth grade education, had difficulty reading, and thus did not pay attention to warning labels.3 Dresser offered evidence that because of the heat in the workplace Lee seldom used a mask or respirator to protect against inhaling the silica dust, even though it bothered him so much that he had to blow it out of his nose and spit it out of his mouth. Lee’s working conditions — a hot, dusty, improperly ventilated foundry — are, in the words of Magro, “other circumstaneefs] tending to show that the improper use would have occurred regardless of the proposed warnings or instructions.” Id. This evidence was sufficient to rebut any presumption that Lee would have heeded a warning by Dresser and that the absence of such a warning was at least a cause, if not the only cause, of Lee’s injury. Although Lee disputed whether he would have heeded a warning label on bags of Dresser products, Dresser was entitled to have that conflict in the evidence resolved by the jury.4 Dresser’s evidence, though certainly not conclusive, raised a factual issue for the jury to resolve. If the jury believed Dresser’s evidence, it could have concluded that Tyler Pipe’s negligence was not only a cause, but the sole cause of Lee’s injuries. It follows, therefore, that the trial court’s exclusion of Dresser’s evidence was reversible error.
Ill
Because this case must be remanded for a new trial, we consider two other matters raised and argued by the parties which will be significant in any retrial of this case. The first is whether Dresser is entitled to have the jury instructed regarding sole cause if that issue is raised by the evidence. The second concerns the manner in which plaintiffs contributory negligence should be submitted to the jury if raised by the evidence.
A
In First International Bank v. Roper Corp., 686 S.W.2d 602 (Tex.1985), this Court held that instructing the jury regarding sole cause in a products liability case was a comment on the weight of the evidence and thus reversible error. We stressed, however, that this holding was limited to cases tried before our decision in Duncan v. Cessna Aircraft Co., 665 S.W.2d 414 (Tex.1984), when no comparative causation rule applied. The basis for this limitation was that prior to Duncan, contributory or third party negligence was a defense in a strict liability case only if it rose to the level of misuse or assumption of the risk. The defendant in Roper, we observed, did not attempt to establish this defense but only to rebut the causation element of plaintiffs ease. In these circumstances, we reasoned, the sole cause instruction added nothing to the charge and even distracted the jury from the issues it was required to decide.
We have never extended Roper to apply to a post-Duncan or statutory comparative causation case, nor could we do so without also extending the reasoning on which it was based. One court has held that Roper does not and should not apply in such cases. Ahlschlager v. Remington Arms Co., 750 S.W.2d 832, 835-836 (Tex.App.—Houston [14th Dist.] 1988, writ denied). See also 3 State Bah of Texas, Texas PatteRN Juky CHARGES PJC 70.03 (1982) (sole cause instruction should be used in products liability case if raised by the evidence). We agree with the court of appeals in Ahlschlager. A *755defendant in a products liability case is entitled to have the jury instructed regarding sole cause if that issue is raised by the evidence. There is no dispute in this case that the instruction Dresser requested was correct in all respects.
B
The court of appeals held that Dresser was not entitled to have the issue of Lee’s contributory negligence submitted to the jury because the issue Dresser requested was not “in substantially correct wording” as required by TexR.Civ.P. 278. The defect, according to the appeals court, was that the contributory negligence question which Dresser requested was not accompanied by an instruction to the effect that a plaintiff has no duty to discover defects in a product or guard against their existence. We have held that plaintiff has no such duty. Shamrock Fuel & Oil Sales Co. v. Tunks, 416 S.W.2d 779, 785-86 (Tex.1967); McKisson v. Sales Affiliates, Inc., 416 S.W.2d 787, 793 (Tex.1967); Duncan, 665 S.W.2d at 482; see also Restatement (Second) op ToRTs § 402A, emt. n (1965); compare Keen v. Ashot Ashkelon, Ltd., 748 S.W.2d 91, 94-96 (Tex.1988) (dissenting opinion by Phillips, C.J., arguing that this rule should be abandoned), with id. at 96-100 (Gonzalez, J., arguing that the rule should be retained).
Assuming that this rule is correct, Dresser had no burden to request that the jury be instructed on the rule. Dresser contends that there was no evidence suggesting that Lee was negligent in failing to discover the risks of using silica products, and therefore there was no need for the limiting instruction. Regardless of whether Dresser was correct in this contention, it was not required to request an instruction which, according to its view of the case, was not raised by the evidence and was not proper. If the evidence raised an issue whether Lee’s own negligence caused his injuries, Dresser was entitled to its requested issues on contributory negligence, and the burden was on Lee to object to the absence of a limiting instruction.
⅜ ⅜ * ⅝! * ⅜
The judgment of the court of appeals is reversed and the case is remanded to the trial court for further proceedings consistent with this opinion.
. In a companion case to Varela, Teakell v. Perma Stone Co., 658 S.W.2d 563 (Tex.), reversing 653 S.W.2d 483 (Tex.App.-Corpus Christi 1983), the defendant did argue that plaintiff's employer's negligence was the sole proximate cause of plaintiff's injuries as a matter of law. 653 S.W.2d at 488-489. However, evidence of the employer’s negligence was admitted at trial, and the jury found that the negligence of both the defendant and the employer caused plaintiff’s injuries. The parties in Teakell did not address the admissibility of evidence of the employer’s negligence, and this Court did not consider the propriety of such evidence in determining whether the employer’s conduct was the sole cause of plaintiff's injuries.
. In a prior case, W.B. Hinton Drilling Co. v. Zuniga, 784 S.W.2d 442 (Tex.App.—Tyler 1989, no writ) (extension granted, but no application filed), the same court of appeals went so far as to suggest that the rule of Varela which requires an employer’s joint tortfeasor to pay for the negligence of both is unjust. Id. at 450. See William C. Powers Jr., Torts—Personal, 38 Sw.LJ. 1, 21-24 (1984). Although an amicus curiae adopts this argument in this case, Dresser does not, and we do not address it.
. The dissent characterizes this sentence as "assuming" that persons with limited educations will not heed warning labels. Post at 755. We assume no such thing; we simply do not assume that such persons will always read and follow instructions. They may, or they may not, and when the evidence concerning whether they did is conflicting, the jury should resolve the conflict.
. Allowing the issue to be submitted to the jury does not, contrary to the dissent's statement, deprive Lee of his legal rights. Lee was entitled to convince the jury that he would have heeded warnings had they been given. Nor is it “elitist”, post at 758, to insist that fact issues be submitted to the jury.