Proximate cause is a complicated way of describing the probability that x leads to y.  If it is more likely than not (preponderance of the evidence) that if x, then y, then proximate cause has been made out.  However, lawyers are less mathematicians than storytellers.  Hence, supposition is a frequent bar to proximate cause,  even

The Big Accounting firms in the US dispense CPA and some legal advice on taxes.  How to parse one from the other is discussed in Boesky v Levine  2021 NY Slip Op 02059 [193 AD3d 403] April 1, 2021 Appellate Division, First Department.

“The motion court properly dismissed as time barred the legal malpractice claims