"couldn't help" vs. "couldn't help but": do they have same meaning here? [closed]

Solution 1:

I puzzled over this for some time and consulted with other native British English speakers. Our conclusion is that "I couldn't help laughing" is how you would describe an automatic reaction to something funny or amusing. "I could not help but laugh" is when laughter may not be the appropriate or expected response, with the implication that laughing is better than crying, screaming or another, more appropriate, but negative, reaction or emotion. Alternatively, "I could not help but laugh" can mean that the circumstances leading to the laughter were such that no other response was possible.