Learn English – Much and many: the opposite of less – fewer debate

This is a problematic question as the words are not clearcut in most peoples minds, but there are cues, and distinctions to be made.

Debate on wikipedia:

Debate or debating is a formal method of interactive and representational argument. Debate is a broader form of argument than logical argument, which only examines consistency from axiom, and factual argument, which only examines what is or isn't the case or rhetoric which is a technique of persuasion. Though logical consistency, factual accuracy and some degree of emotional appeal to the audience are important elements of the art of persuasion, in debating, one side often prevails over the other side by presenting a superior "context" and/or framework of the issue, which is far more subtle and strategic.

Argue on wikipedia:

In philosophy and logic, an argument is an attempt to persuade someone of something, by giving reasons or evidence for accepting a particular conclusion.[1][2] The general structure of an argument in a natural language is that of premises (typically in the form of propositions, statements or sentences) in support of a claim: the conclusion.[3][4][5] Many arguments can also be formulated in a formal language. An argument in a formal language shows the logical form of the natural language arguments obtained by its interpretations.

Thus a debate is:

• More formal
• More intellectual
• Normally concerns factual events, or theories
• Concerned with persuading the opposing party to an alternate viewpoint

To argue however is not the same as an arguement. Nor is the logical definition of 'argue' the same as what is commonly referred in public. One can argue the case of XYZ say in law or physics, or one can argue on the street ( in which case bickering would be a more appropriate word ).

For example Alice had an arguement with Bob where she accused him of paranoia, would not be considered a debate. Here Alice argues the point that Bob has paranoia. One can argue at a debate, and an argument, but an arguement is not a debate.

Arguments are thus:

• Informal
• Usually personal, though not always
• Not always concerned with the factual correctness
• Can be about things both parties are aware of, thus no opposing viewpoints, e.g. a row between a man and wife who have cheated on each other, would not be a debate, as they are both aware and agree that adultery took place.

In most of the cases of 'arguments', one could substitute another word such as row, tiff, bickering, and various other words. Where debate is concerned, one could use the word arguement, but not words such as row or bicker.

Debate has method. Argument does not necessarily.

Fewer is used when referring to countable quantities (in which case the noun is usually in plural), and less is used when referring to uncountable quantities (in which case the noun is usually in singular). So I would say fewer cows, but less milk.

If I understand correctly, a ply is a layer. So plies would be countable quantity, just like layers, and I would say fewer plies as you suggested yourself.

However, I can imagine that there could be situations where the word ply is sometimes used informally for something made of layers, for example as a shortening of plywood. In which case you could say ''less ply'' in this context, as it would actually be short for ''less plywood'', which is fine.