Jenkins, P. J.
(After stating the foregoing facts.) With reference to the rulings made in the last three divisions of the syllabus, relating to exceptions to the charge on the subject of negligence,—it is provided by the Civil Code (1910), § 4426, that, “if the plaintiff by ordinary care could have avoided the consequences to himself caused by the defendant’s negligence, he is not entitled to recover. But in other cases the defendant is not relieved, although the plaintiff may in some way have contributed to the injury sustained.” In Americus &c. R. Co. v. Luckie, 87 Ga. 6, 7 (13 S. E. 105), it was held that “the ‘other eases’ referred to are manifestly those in which the plaintiff could not by ordinary care have avoided the consequences of defendant’s negligence. In cases of that kind, both parties being at fault, the damages are apportioned.” But the rule which precludes the plaintiff from any re*209covery whatever where he has failed to exercise ordinary care to avoid the results of the defendant’s negligence, as set forth m the first sentence of section 4436, “is a different principle from what is known as the doctrine of contributory (or more accurately speaking) comparative negligence” and diminution of damages, as referred to in the latter sentence of that section, and (with reference, to damages by railroad companies) in section 3781. Cen. of Ga. Ry. Co. v. Burton, 33 Ga. App. 199 (3) (135 S. E. 868); Lamon v. Perry, 33 Ga. App. 218 (4) (125 S. E. 907). Under the first rule, where the defendant has failed to exercise ordinary care, if the plaintiff himself also failed to exercise ordinary care to avoid the consequences caused by the defendant, the plaintiff can recover nothing. But under the latter rule, where the defendant failed to exercise ordinary care, the plaintiff, notwithstanding his own fault, can recover partial damages diminished and proportioned according to the degree of his negligence compared with that of the defendant, provided the fault of the plaintiff does not also amount to a lack of ordinary care, and does not equal but is less than the fault of the defendant. Cen. R. Co. v. Newman, 94 Ga. 560 (1) (31 S. E. 319); Davies v. West Lumber Co., 33 Ga. App. 460 (2 a) (123 S. E. 757); Cen. of Ga. Ry. Co. v. Burton, supra. A confusion of these two distinct rules in a charge is error. Americus R. Co. v. Luckie, supra (87 Ga. 7).
“When a judge undertakes to charge the law upon any subject, he must charge all of it upon that subject that is material and applicable to the case.” Hinson v. Hooks, 27 Ga. App. 430 (108 S. E. 822). This rule is in no wise in conflict with that expressed in Wilson v. Small and Ga. Granite Gorp. v. Union Granite Go., supra, that a failure to charge a legal principle in the same connection with another correct and pertinent rule is not erroneous; for the latter rule assumes that the instructions on the rule given are correct and stated with sufficient completeness not to confuse the jury. In the instructions now under review the judge obviously was not confining himself to the rule set forth in the first sentence of section 4436, wholly precluding the plaintiff’s recovery, but was also dealing with the distinct rule of comparative negligence, partially but incompletely stated in that section. While the judge was under no duty, in the absence of any raising of the issue by the pleadings or of any request to charge, to deal with the rule *210of comparative negligence, nevertheless when he did deal in part therewith, it became his duty to charge with accuracy the essentials of that principle. The instructions as given failing'in this respect, and being subject to the construction that the plaintiff could be allowed full, instead of diminished, damages, if “the greater cause of the injury was due to the negligence of the defendant’s agent,” was erroneous. In view of the closeness of the issues of negligence involved under the evidence, it was, for this reason alone, error to refuse a new trial to the plaintiff. See also Cen. R. v. Brinson, 70 Ga. 207, 210 (8); G. S. & F. Ry. Co. v. Overstreet, 17 Ga. App. 629, 630 (5 d) (87 S. E. 909).
Judgment reversed.
Stephens and Bell, JJ., concur.