He describes the style he did like as "Euler's style, so to speak". What was Euler's style in this context? i.e. as opposed to epsilons and deltas?
He describes the style he did like as "Euler's style, so to speak". What was Euler's style in this context? i.e. as opposed to epsilons and deltas?
Euler was a master manipulator of formal expressions; don't think it bothered him very much whether, e.g., an infinite series converged or not. (Unfortunately don't remember a source for this offhand -- maybe a leftover impression from having read ET Bell's book long ago? I also don't know how reliable Bell is.)
Edit: added semi-source
Cauchy is the one who introduced rigor to calculus with the formalization of limits, including epsilons and deltas, a full century after Leibniz and half a century after Euler.