“True law is right reason in agreement with nature; it is of universal application, unchanging and everlasting; it summons to duty by its commands, and averts from wrongdoing by its prohibitions…Whoever disobeys is fleeing from himself and denying his human nature, and by reason of this very fact he will suffer the worst penalties, even if he escapes what is commonly called punishment.”

As Cicero thus reminds us in his Republic, rational humans seek to find out what’s true and act accordingly. We angsty college students, grappling with nascent faculties of reason, especially a love to think and debate—and sometimes even berate our comrades—are in search of universal truth.

When it comes to such quests for truth, some of the most contentious and provocative discussions surround how to deal with young, old, or incapacitated clumps of cells that may or may not be alive. Unfortunately, there exists sufficient confusion surrounding the biological definition of life where people create enemies out of budding rhetoricians before they even get to the meat of their discussion. This premature misunderstanding is compounded when not only youth, but also seasoned academics, participate in clouding objectivity, describing the definition of life as a belief “based on…religious or philosophical theories.”

Contrary to such obscure academics’ opinions, we can and should agree upon a biological definition of life prior to debating the ethical consequences of an object being alive. Certainly there is a variety of perspectives on the meaning of existence across philosophical schools of thought; this fact does not mean we ought to disagree from the get-go on what constitutes a biological definition of life.

So before we debate what ethical principles bind us in interacting with a living being, here is a simple algorithm to determine whether any given clump of cells is actually alive.

1. Is it made of cells?

Life is organized, with physical boundaries encasing each living cell. If your lump of tissue does indeed happen to be a clump of cells, you’re 20% of the way to proving that it’s alive. This physical organization is in part necessary to ensure that step 2 can be satisfied.

2. Does it tend toward homeostasis?

Homeostasis is a state of equilibrium which allows cells to carry out biological functions in a certain range of conditions, such as intracellular temperature, pH (acidity), or salinity. This allows for all other cell parts to carry out all biological functions, culminating in the following three steps.

3. Does it respond to external stimuli?

If you have arrived at this step and you look closely at your clump of homeostatic cells, you will notice that it is metabolizing, or making energy conversions by building up and breaking down compounds. To ensure the success of these processes which keep the cells alive, the cells will make necessary adjustments when they sense external stimuli. Responses include motility or simply altering rates of metabolism to sustainable levels. A cell thus stabilized is better poised to satisfy step 4.

4. Does it grow?

You guessed it. In this step, your stimuli-responsive, homeostatic cells increase in size. Growth is necessary to achieve the sexiest step of all: step 5.

5. Does it reproduce?

Fear not, even if your clump of cells is underage. Your mass of organic tissue still satisfies this step even if it is only performing mitosis, or regular cell division within a single organism. Some organisms also do perform meiosis, which allows for sexual reproduction, but sexual abilities are not necessary to establish the presence of life.

If you return a “yes” answer to all five questions, your collection of matter is a living organism. Make use of this simple guide before you debate the great questions of life with your fellow pensive youth or hopped-up academics. All debaters involved can benefit greatly from agreeing upon a specific, scientific definition for that which constitutes a biological lifeform. The above is consistent with NASA’s working definition of life as well as the slightly broader Darwinian definition. The above perspective is simplified yet operational, and a cursory glance at the relevant biomedical theory will assure its users that the literature is replete with evidence in support of this operational definition of life.

It is important to keep in mind, of course, that this five-step biological definition of life neither precludes nor favors any certain moral perspective. For example, sending a zygote, brain-dead trauma victim, or terminally-ill grandfather through the algorithm will repeatedly produce the result that the given clump of cells constitutes life. However, there remains a wide variety of debatable ethical consequences of this fact.

In other words, the five-step system above makes no moral claims. It does not define consciousness. It does not define consent. It does not define humanity. It does not define murder.

But it does biologically define life, and that should prove incredibly useful as an agreeable foreground to more complicated ethical discussions. Rather than allowing your opponents to waffle about by throwing basic vocabulary into the pit of obscure subjectivity, pin them down to an objective definition. From there, you and your sparring partners may seek much loftier heights of ethical philosophy.

What moral principles are invoked upon recognizing a living organism? Under what conditions are there any moral imperatives on interactions with life? The responsibility of answering these questions is entrusted to your capable hands. Best of luck in your search for universal truth, and—of course—happy debating.