Hope this clears it up:
In The principle of tolerance, Jacob Bronowski discusses a vital but neglected characteristic of science: that ''all information is imperfect'', and ''our ability to work and act in the real world depends on our accepting a tolerance in our recognition and in our language''. The nineteenth century ideal that "science should speak the perfect factual truth has turned out to be inaccessible". But this should not be a cause for regret, because "if things had to be identical before you could recognize them, you would never recognize anything at all". The principle of tolerance is the judgment that two instances are sufficiently similar that we can treat them as the same for present purposes. "Tolerance - is the essential safeguard, the essential degree of coarseness which makes it possible to work with abstract entities in the real world". Too much tolerance and you are misled by random variation; too little tolerance and you lose valuable information. The most beneficial degree of tolerance must be a matter of judgment because it cannot be determined in advance. So, the best level of tolerance is known only retrospectively, by comparing the rate of progress of science when a greater or lesser degree of tolerance is assumed. The judgment of tolerance which led to the fastest scientific progress is justified as having been the best. Science therefore needs to tolerate different judgments of tolerance among scientists, allowing a multiplicity of levels of tolerance to coexist and compete. Bronowski's principle of tolerance locates the roots of science in the domain of human creativity, in the necessity for personal judgment in science, and in the provisional and progressive nature of scientific truth: "You have to tell the truth the way you see it. And yet you have to be tolerant of the fact that neither you nor the man you are arguing with is going to get it right".
