Thus, where Zeller says that the Greek philosophers confounded the objective with the subjective because they were still imperfectly separated from Nature, we seem to have come on a less ambitious but more intelligible explanation of the facts, and one capable of being stated with as much generality as his. Not only among the Greeks but everywhere, culture is more or less antagonistic to originality, and the diffusion to the enlargement of knowledge. Thought is like water; when spread over a wider surface it is apt to become stagnant and shallow. When ideas could only live on the condition of being communicated to a large circle of listeners, they were necessarily adapted to the taste and lowered to the comprehension of relatively vulgar minds. And not only so, but the habit of taking their opinions and prejudices as the starting-point of every enquiry frequently led to the investment of those opinions and prejudices with the formal sanction of a philosophical demonstration. It was held that education consisted less in the acquisition of new truth than in the elevation to clearer consciousness of truths which had all along been dimly perceived. To the criticism and systematisation of common language and common opinion succeeded the more laborious criticism and systematisation of philosophical theories. Such an enormous amount of labour was demanded for the task of working up the materials amassed by Greek thought during the period of its creative originality, and accommodating them to the popular belief, that not much could be done in the way of adding to their extent. Nor was this all. Among the most valuable ideas of the earlier thinkers were those which stood in most striking opposition to the evidence of the senses. As such they were excluded from the system which had for its object the reorganisation of philosophy on the basis of general consent. Thus not only did thought tend to become stationary, but it even abandoned some of the ground which had been formerly won.