"Some there are that torment themselves afresh with the memory of what is past; others, again, afflict themselves with the apprehension of evils to come; and very ridiculously both - for the one does not now concern us, and the other not yet ... One should count each day as a separate life."

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Where danger shews it self, apprehension cannot, without stupidity, be wanting; where danger is, sense of danger should be; and so much fear as should keep us awake, and excite our attention, industry, and vigour; but not to disturb the calm use of our reason, nor hinder the execution of what that dictates.

— John Locke