Originally Posted by
Pilot DAR
if you can maintain the required visibility and minimum altitude by flying round or under them (over is less well accepted).
Yes, well, I went over a little cloud once by going up ... into Luton's airspace. No terribly great harm done, as I was talking to a Luton controller at the time, who was helping me get home after a turn-back through rather worse weather than forecast.
[There's also the "if you can see through it you can fly through it" thing, but I wouldn't dream of mentioning that anywhere a newbie might read it. Just in case, for the avoidance of doubt, they try it and kill themselves.]