Ultra Vires nihil aggrediendum.

We should be cautious of attempting what we have not ability to accomplish. A little wariness, prevents great weariness. The adage was used by Paris to Hector, advising him against a personal conflict with Achilles, and it had been well if he had attended to the admonition, as he lost his life in the contest. It is not, however, on all occasions to be followed, as without trial it is not always easy to know how far our ability or power extends; and where a great object is proposed, it is not to be neglected from an apprehension, inspired, perhaps, by timidity of its failing. In magnis et voluisse sat est, it is honourable even to have attempted a great and noble act; that is, if the attempt has been persevered in with becoming spirit, and the failure, if it should not succeed, has not been owing to negligence. We may oppose to this adage, Nothing venture, nothing have.